Personal Mobility Vehicle Research Articles

ステアバイワイヤ機構を用いた小径自転車の走行安定性に関する実験

From the view point of the environmental protection and convenience for transportation, a bicycle is one of the effective forms of the personal mobility vehicles. It is known that a small wheel bicycle running at low speed has less upright stability. In this study, steer-by-wire system is used to steer and stabilize a small wheel bicycle. In a bicycle with Steer-by-wire system, the mechanical connection between handlebar and steer-assembly is replaced by electronic connection with actuators, sensors and a controller. The system can enhance the upright stability of a bicycle by a control system. This study aims to enhance the upright stability of a small wheel bicycle at low speed. Firstly, we designed the mechanism of steer-by-wire system. The system has tracking torque and stabilizing torque. The former reduces the difference between handle and steer angle to a minimum. The later makes a bicycle upright when it leans. Secondly, we made the experimental model of the small wheel bicycle with steer-by-wire system. Finally, we conducted a running experiment to evaluate the tracking performance of steer-by-wire system. From the time history response of the handle and steer angle, the good performance was confirmed.

ステアバイワイヤ機構を用いた小径自転車の直立安定性に関する基礎検討

From the view point of the environmental protection and convenience for transportation, a bicycle is one of the effective forms of the personal mobility vehicles. It is known that a small wheel bicycle running at low speed has less upright stability. In this study, Steer-by-Wire system is used to steer and stabilize a small wheel bicycle. In a bicycle with Steer-by-wire system, the mechanical connection between handlebar and steer-assembly is replaced by electronic connection with actuators, sensors and a controller. The system can enhance the upright stability of a bicycle by a control system. This study aims to enhance the upright stability of a small wheel bicycle at low speed. Firstly, we conducted the eigenvalue analysis to evaluate the upright stability of a bicycle and examined the difference of the stability between a bicycle with normal wheel and a small wheel one. Secondly, we designed the mechanism of Steer-by-Wire system and examined the effectiveness of Steer-by-Wire system in a small wheel bicycle. Finally, we investigated the behavior of a small wheel bicycle with Steer-by-Wire system when the system is subjected to disturbance torque. As a result, we found that Steer-by-Wire system could enhance the upright stability of a small wheel bicycle at a low speed.

パーソナルモビリティビークル用全方向移動球体式アクチュエータの設計と試作

パーソナルモビリティビークル用全方向移動球体式アクチュエータの設計と試作

Mobility Support System for Personal Mobility Vehicles

<div class=""abs_img""><img src=""[disp_template_path]/JRM/abst-image/00270006/14.jpg"" width=""300"" /> Transportation system of PMVs by MSS</div>The mobility support system (MSS) that we propose expands the field of activities of personal mobility vehicles (PMVs). The system consists of a server, an ultrasonic wave (UW) system that provides self-localization in facilities, and an infrared ray (IR) system that supports passing through narrow spaces in facilities such as station ticket wickets for PMVs. Results of experiments confirmed the feasibility of the system.

Evaluation of the Effects of a Personal Mobility Vehicle on Multiple Pedestrians Using Personal Space

Personal mobility vehicles (PMVs) have increasingly attracted research interest as new individual transportation vehicles that are environmentally friendly, compact, and convenient to use. It is important to ensure the safety and comfort of pedestrians sharing space with PMVs. In this paper, we developed a simulation model considering the interaction between a PMV and pedestrians, and investigated the effects of a PMV in pedestrian flows using the concept of personal space (PS), which is the space in which invasion by others induces a psychological strain. To estimate the mutual effects of a PMV and nearby pedestrians, the invasion ratio and crossing time are introduced as indexes. Furthermore, to ensure pedestrians are comfortable in the presence of a PMV, we proposed an assistance system for a PMV. Simulation results revealed that the invasion of PS increases with increasing pedestrian density. Additionally, experimental results showed that the levels of discomfort and fear that pedestrians felt toward a PMV are also affected by pedestrian density. Finally, the effectiveness of the assistance system was confirmed, particularly for low pedestrian densities.

Driving Performance and User's Evaluation of Self-Balancing Personal Mobility Vehicle with a Pedal Driving Mechanism

In this paper, we propose a self-balancing personal mobility vehicle with a hybrid driving mechanism, called as Wi-PMP, and discuss its features from the perspectives of its power-assist driving performance and a rider's evaluation. The mobility vehicle consists of a wheeled inverted pendulum type mobile platform, and a hybrid driving mechanism that can use human and motor power together for driving. By performing a bump driving, a slope driving, and a outdoor driving experiment, we confirm that the proposed hybrid mechanism is valid for the integration of human and motor power, and is effective to increase the driving power and reduce electrical load on motors and batteries. We conducted several experiments to investigate the rider's evaluation on a sit-riding method compared to a stand-riding one. The questionnaire results showed that a rider felt more comfortable in the case of the sit-riding method when getting on and off, and when driving the mobility vehicle. This implies that riding-type self-balancing vehicles such as Wi-PMP have the potential to become familiar personal mobility vehicles in daily life.

Comparative Traffic Analysis between Electric Personal Mobility and Partial Autonomous Vehicle Using Agent-Based Model

Comparative Traffic Analysis between Electric Personal Mobility and Partial Autonomous Vehicle Using Agent-Based Model

An Evaluation Analysis on Three-Wheeled Personal Mobility Vehicles

Personal mobility vehicles are proposed as a new category of transportation device that offers several potential benefits to solve the current problems, such as mobility issues of the elderly, downtown area revitalization, and development of low-carbon transport. This paper aims to explore basic attitude of the general public to understand how people think about three-wheeled personal mobility vehicles. Using the surveys data on i-REAL conducted in Toyota, a discussion is made by employing Quantification Theory and Semantic Differential Method. Moreover, textual data derived from the survey are classified by applying Text Mining. Furthermore, conclusions are drawn and suggestions for further work are made. As a conclusion from the comparative analysis between the unexperienced and experienced groups, the experience brings people to make different evaluations so that the test rides are very important to know the true answers. The analysis on the experienced people shows that the elderly highly evaluated the hobby factors, the male highly evaluated the practice factors and the weather condition seems being a key factor for the current model.

Semiautonomous Control of Personal Mobility Based on Passenger's Collision Avoidance Judgment Timing

Abstract We have implemented a personal mobility (vehicle) that has semiautonomous control by estimating the avoidance direction and the avoidance judgment timing. In coexist space of pedestrians and passengers on personal mobility, it is necessary to realize safety collision avoidance by moving the mobility. Therefore, we estimate avoiding direction from pedestrianfs body parts and implement semiautonomous collision avoidance system. And we have collision avoidance experiments between a pedestrian and a passenger on personal mobility. We evaluate important pedestrianfs body parts for avoiding judgment and avoidance judgment timing. As a result, passengers gaze at pedestrian's lower body parts in semiautonomous control, and avoidance judgment timing is delayed about pedestrian's one step. We have proposed a model of passenger's motion perception and vision guidance on personal mobility.

立ち乗り型パーソナルモビリティ豊田市実証実験の紹介

立ち乗り型パーソナルモビリティ豊田市実証実験の紹介

Modeling and simulation of multiple personal mobility vehicles in pedestrian flows using personal space

Modeling and simulation of multiple personal mobility vehicles in pedestrian flows using personal space

A213 自律隊列走行のためのパーソナルモビリティビークルの自動追従システム(OS11 自律知能無人ビークルの運動と制御3)

A213 自律隊列走行のためのパーソナルモビリティビークルの自動追従システム(OS11 自律知能無人ビークルの運動と制御3)

人の運動特性を利用したサドル型身体動作インタフェースによるパーソナルモビリティビークルの操作

This paper proposes the human body motion interface for personal mobility vehicle including the user's twisting motion. First, saddle is attached on the personal mobility vehicle using the seat post which has the universal joints at the attachment portion. The universal joints have three rotational joints where the potentio meters are attached on each. By hip motion, the joints are moved. The potentio meters detect these rotations. Next, we introduced the sigmoid function to connect the motion of hip and the velocity of the personal mobility vehicle. Finally, the experiment was conducted to confirm the usability. In the experiment, the control interface was prepared which doesn't use the twisting motion of the hip. The subjects drive the personal mobility vehicle on the figure 8 course layout by using proposed interface and control interface. The lap times were measured in both interface and compared. After driving the vehicle, the paired preference test was conducted. The lap time using proposed interface was shorter than the control interface, and the paired preference test showed the proposed interface is intuitive.

Improved Gait Algorithm and Mobility Performance of RT-Mover Type Personal Mobility Vehicle

We have developed a personal mobility vehicle (PMV) with four driven wheels that is capable of negotiating obstacles with a leg motion mechanism. When obstacles are encountered, wheels are lifted, moved ahead in a stepping-like motion, and lowered back down, thereby allowing the PMV to advance further. In our previous paper, we discussed the principle of the gait algorithm used by our PMV, in which wheels are utilized as legs to negotiate obstacles. In the original algorithm, when the wheels encountered terrain that might require leg motion to traverse, the system determined whether such motion was applicable and, if it was, orchestrated a series of leg motions. However, there were terrains that could not be negotiated using the original algorithm. In this paper, we propose an improved gait algorithm, in which when the vehicle encounters terrain intractable by leg motion with its current posture, the vehicle changes its posture until it can traverse that terrain. We verified the effectiveness of the improved gait algorithm through a variety of mobility tests with a passenger. In addition, we present numerical data on the range of terrain topologies that could be negotiated by the proposed algorithm.

3103 次世代パーソナルモビリティの構築に関する研究(OS10-2 ドライバ特性と車両運動制御の調和,OS10 アドバンティシンポジウム,オーガナイズド・セッション(OS))

In recent years, a ratio of owner passenger cars in all car-registrations in Japan exceeds more than 70%. Therefore, the owner-cars are as very important means of transportation system. On the other hand, the boarding rate per a vehicle decreases gradually, and, recently, it has become about 1.3 persons per one vehicle. From these situations, a development of the personal mobility vehicle as one of the transportation tools is effective. From the reasons, various kinds of personal mobility vehicles are proposed in recent years. From a viewpoint of road share reduction and of energy consumption, we propose a personal mobility vehicle with rolling-motion such as two-wheeled vehicles. Since the steering system is connected by linkages between steering system and rolling suspension system, driver controls not only steering angle but also rolling angle at the same time using steer angle. As the result, it is shown that the link ratio realizes very large characteristic region by changing according to speed.

3210 パーソナルモビリティ用シミュレータ構築に関する研究(OS9-1 シミュレータシステムの開発,OS9 ビークルシミュレータの開発と応用,オーガナイズド・セッション(OS))

3210 パーソナルモビリティ用シミュレータ構築に関する研究(OS9-1 シミュレータシステムの開発,OS9 ビークルシミュレータの開発と応用,オーガナイズド・セッション(OS))

3P1-I10 不整地移動可能なパーソナルモビリティビークルと移動支援システムに関する基礎的研究(プロジェクトサマリー)

3P1-I10 不整地移動可能なパーソナルモビリティビークルと移動支援システムに関する基礎的研究(プロジェクトサマリー)

Measuring the Acceptability of Self-Balancing Two-Wheeled Personal Mobility Vehicles

Many studies on the development, on-road compatibility, and market potential of personal mobility vehicles have been conducted in recent years. This study focuses on the social acceptability of personal mobility vehicles by the general public, which is a key factor in the future introduction and implementation of these vehicles. Using survey data collected from 124 respondents from the city of Toyota, this study empirically explores the attitudes of the general public toward self-balancing two-wheeled vehicles and differences in the public’s acceptance of such vehicles before and after using them. Potential uses of these vehicles include tourism and excursions, short-distance trips in downtown areas, and traversing within buildings. Causal relationships between the acceptability of self-balancing two-wheeled vehicles and attitudes toward various characteristics of these vehicles are also analyzed in this study. The empirical results indicate that attitudes toward self-balancing two-wheeled vehicles increase after using the vehicles. The causal relationships between the acceptability of and attitudes toward self-balancing two-wheeled vehicles are identified using structural equation modeling.

Gait algorithm of personal mobility vehicle for negotiating obstacles

Purpose: Personal mobility vehicles (PMVs) are under active development. Most PMVs are wheel-driven, a mode of transport notable for its efficiency. However, wheeled PMVs tend to have poor mobility against negotiating obstacles. The four-wheeled vehicle RT-Mover PType 3 has been developed featuring wheeled legs capable of leg motion. This allows the PMV to overcome uneven terrains, including a step approached at an angle, which ordinary wheelchairs cannot negotiate. Method: This article discusses a gait algorithm in which a leg executes the necessary leg motion when optionally presented with obstacles on a road. In order to lift a wheel off the ground and perform a leg motion, the support wheels must be moved to support points to ensure that the vehicle remains stable on three wheels. When moving towards the target support point, a wheel may encounter another obstacle, and a response method for this case is also described. Results: To assess the gait algorithm, several configurations of obstacles were used for performance tests with a passenger. The capabilities of the PMV were demonstrated through experiments. Conclusion: We proposed a novel gait algorithm for our PMV and realised the proposed motion pattern for PMV-based negotiating obstacles.Implications for RehabilitationOur single-seat personal mobility vehicle, RT-Mover PType 3 features wheels attached on legs capable of performing leg motion, which allows the vehicle to traverse rough terrains in urban areas.We proposed a gait algorithm for RT-Mover PType 3 consisting of a series of leg motions in response to rough terrain. With this algorithm, the vehicle can traverse not only randomly placed obstacles, but also a step approached at an oblique angle, which conventional powered wheelchairs cannot navigate.Experiments with a passenger demonstrated the effectiveness of the proposed gait algorithm, suggesting that RT-Mover PType 3 can expand the mobility and range of activities of wheelchair users.

Feasibility study of a green energy powered thermoelectric chip based air conditioner for electric vehicles

Traditional compressed-refrigerant air conditioning systems consume substantial energy that may reduce the driving performance and cruising mileage of electric vehicles considerably. It is crucial to design a new climate control system, using a direct energy conversion principle, to further aid in the commercialization of modern electric vehicles. A solid state air conditioner model consisting on TECs (thermoelectric chips) as the load, DSSCs (dye sensitized solar cells) as the renewable energy source and high power LiBs (lithium-ion batteries) as an energy storage device are considered for a personal mobility vehicle. The power management between the main power net and the solid state air conditioner interface is designed with an outer proportional-integral controller and an inner passivity based current controller with a loss included model for perfect tracking. This model is intended to comprise thermal and electrical elements which can be tunable for performance benchmarking and optimization of a solid state air conditioning system. Dynamic performance simulations of the solid-state air conditioner are performed, alongside guidelines for feasibility.